By the Book

Survival of the fittest

What were we like 100,000 years ago? Not too much different than the way we are today, according to this month's book. That is, our bodies were about the same except they were in better shape then and subject to fewer diseases than they are now.

That is the message of Daniel E. Lieberman's "The Story of the Human Body: Evolution, Health and Disease."

He is a Harvard professor of biology who had the good sense to write about the science and history of our physical bodies in a conversational style. Reading this book is like sitting down with a knowledgeable person and talking about ourselves -- not about immediate concerns, but how we look in the big picture of evolution as we understand it.

Lieberman is a scientist who accepts evolution as simply change over a period of time. The changes depend on their ability to promote survival or natural selection. His concern is the human body that managed to survive more than 100,000 years ago in Paleolithic time was one that suited the conditions at that time.

The earliest human fossils and very primitive societies today show that those humans led very active lives with most of their time spent hunting and gathering. They could make tools out of stone and they moved about a great deal. It has been proposed that they walked about nine miles a day in the search for food, bending, climbing and digging to get at it.

While our culture has evolved greatly since then, making life much easier, Lieberman says there is little evidence that the human body has changed that much. To him, this means that our reduced physical activity is so harmful, it leads to diseases that threaten our survival.

He shows that today's common diseases -- like cancer, type 2 diabetes and heart conditions -- were not problems thousands of years ago. It is true that people lived shorter lives without medical care and faced constant peril. But, on the other hand, their activity led to greater fitness.

He argues that our prevalent diseases today are better dealt with through prevention. All these diseases were extremely rare 100,000 years ago, as was obesity. A return to the activity level of the time of our evolutionary success, he believes, would be a proper prescription for the ills of our modern age.

This book shows how the body works to maintain itself. This is especially true for our bones. No material has been developed by our advanced society that comes close to the ability of bone to restore itself. But it all depends on activity.

The book is so clearly written with as many convincing arguments that it deserves to be widely read. It may even motivate us to move around a little more.

"The Story of the Human Body: Evolution, Health and Disease" by Daniel E. Lieberman is at the Bella Vista Public Library.

* * *

Stenson is an award-winning teacher from Chicago, where he taught for 30 years. He has resided in Bella Vista for 20 years. He serves on the Bella Vista Library Foundation Board and the library's Book Selection Committee. The opinions expressed in this column don't necessarily reflect the views of the newspaper.

Community on 07/23/2014